With confusion surrounding whether the goal had been awarded or not, PAOK president Ivan Savvidis walked onto the pitch accompanied by bodyguards wearing a handgun in a holster on his waist. The match was subsequently abandoned as Savvidis was escorted from the field.

"We have decided to suspend the Championship indefinitely," Greece's Deputy Culture and Sports Minister Georgios Vassiliadis told National Greek broadcaster ERT following a meeting with the Prime Minister Alexis Tsipras.

"We are in communication with UEFA and the Championship will not resume unless there is a new and clear framework agreed by everyone so we can move forward with rules and regulations. We are not going back, we continue the fight for transparency and a better football."

Earlier Vassiliadis told CNN Sport that "scenes where armed officials enter the sport field send us many years backwards. Such extreme phenomena demand courageous decisions.

"We will not allow to anyone to derive us from our target even if we need to take tough decisions in communication with the UEFA."

World governing body FIFA told CNN in a statement that it was aware of the incident and "fully condemns such behavior," though "as the incident occurred in domestic competition, all disciplinary action falls under the jurisdiction of the Greek Football Association."

"Given the sensitive nature of football governance in Greece with the recent match fixing scandals, UEFA and FIFA may assume not only jurisdiction, but also a supervisory role in terms of the proceedings at national level," Ioannidis told CNN Sport.

He added: "It is also worth noting that current laws and regulations in Greece do not even allow police officers to carry firearms when inside a sporting ground, let alone allowing civilians to do so."

"It means that the provocative headlines in certain media are totally untrue. He carries weapons as he has a permission for it. It's not prohibited in Greece."

CNN was not immediately able to reach Savvidis for comment.

In a written statement posted to the club website, PAOK said: "Ivan Savvidis is preparing to take all necessary steps to protect the club and all his executives and associates from the threats and attacks they are suffering."

Dubbed the "Double-headed Eagles Derby" on account of the clubs' badges, the rivalry between PAOK and AEK has a fierce and storied history.

AEK currently lead the Superleague -- with PAOK in third -- meaning Sunday's game was crucial in the Greek title race's likely outcome.

The Greek Superleague lists the result as a 1-0 PAOK victory, though it remains unclear whether this scoreline is final.

Greece wasn't the only major European league affected by a pitch invasion over the weekend.

English Premier League club West Ham United has launched an inquiry after a number of fans invaded the pitch during Saturday's 3-0 defeat by Burnley at the London Stadium.

"West Ham United have immediately launched a full and thorough investigation into the incidents which marred the second half of today's match and are committed to taking decisive and appropriate action," said a club statement on Saturday.

"An emergency meeting has been called with all London Stadium stakeholders. There will be no further comment at this time."

West Ham is 16th in the table, three points above the relegation zone.